Cardiac exerciser



Sept. 22, 1970 A. M. OLSON E-TAL CARDIAC EXERCISER Filed DeC. E, 1968 3Sheets-Sheet 1 V INVENTOR. ALBERT M. OLSON T OHNSON EVERETT H. J

BY (M ATTORNEYS Sept. 22, 1970 A. M. OLSON EFAL 3,529,474

CARDIAC EXERC I S E R Filed Dec. 5, 1968 I 5 Sheets-Sheet 2 FIGBINVENTOR. ALBERT-M. OLSON E\}$RETT H. JOHNSON ATTORNEYS Sept 22, 1910QLSQN ETAL 3,529,474

CARDIAC EXERCISER Filed Dec. 5, 1968 s Shets-Sheet a whfL 11 INVENTOR.

ALBERT M. OLSON EggRETT H. JOHNSON 060 4 1O ATTORNEYS United StatesPatent Filed Dec. 5, 1968, Ser. No. 781,492 Int. Cl. A03b 21/00; G011/02 U.S. Cl. 73-379 6 Claims ABSTRACT OF THE DISCLOSURE An exercisingergometer. A pair of handrails and a central column are supported on abase. In the column are a pair of hydraulic cylinders, each having apiston and a connecting rod, and a pedal on each side of the column isconnected to one connecting rod. There is means for limiting the strokeof each piston and of the pedal associated therewith. An hydrauliccircuit connects the two cylinders and includes (a) load valve means forcontrolling the pressure transmitted, for causing one pedal to rise whenthe other is depressed and (b) means for measuring the work expended inmoving the pedals.

This invention relates to an improved cardiac exerciser.

Heretofore there has been no accurate way of measuring, in smallhospitals, clinics, or private cardiologists oflices, the exact amountof energy expended by the exercise which is used in conjunction withelectrocardiograph machines. Although tracings were taken before andafter exercise, there was, therefore, no way of determining the extentof the exercise which resulted in the changes noted. Attempts to definethe extent of exercise by merely counting the number of steps or jogstaken in a walk-inplace or run-in-place exercise, whether timed or not,were not sufficient, because the amount of such exercise depends uponthe weight of the person involved. The important thing is the actualenergy expended. Such ergometers as do exist have been very expensive,very large, and not suitable for an ordinary physician who must keep hisequipment in a relatively small examination room. Some expensive devicesdesigned for physicians have measured degrees of incline and the speedof walk on treadmills but have still not measured the energy expended.

The present invention is a relatively small piece of equipment whichmeasures accurately how much energy is expended during certainexercises, while at the same time being relatively inexpensive andcapable of being kept in a doctor's small examination room. With thisequipment, an electrocardiogram can be taken before exercise on a normalelectrocardiograph machine; then the patient exercised for a definitenumber of foot pounds of energy per unit of time, and a newelectrocardiogram taken for a comparison. Thus the comparison is muchmore meaningful than when the extent of exercise remained unknownSimilarly, the patient can be placed on a diet to lose a certain amountof weight, or can be placed on a particular therapeutic regimen, and theabove procedure repeated to see what improvement has occurred.

The exercising device of this invention is helpful in tracing the originof chest pains which may be only vague. The patient can be exercised tothe point of pain production and a tracing on the electrocardiogram madeimmediately, so that the doctor can observe both how many foot pounds ofenergy were expended and also the change in the tracing. Then, followinga therapeutic program, a repetition of the test can enable the doctor tosee how much more work the patient can do before pain commences orbefore an electrocardiographic change is "ice evident. Heretofore,physicians could only estimate the activity and could not reproduce thesame activity at a later date because the patient may have gained orlost an appreciable amount of weight in the meantime. In addition,cardiac output studies can be made during cardiac catheterization,before, during, and after exercise. Heretofore, the available equipmenthas been clumsy, hard to anchor to an X-ray table, and inaccurate.Equipment embodying the principles of the present invention may befastened securely to a catheterization table, and may be small enoughnot to interfere with extensive monitoring equipment. Moreover, it isaccurate. Also, simultaneous evaluation of cardiac output and cardiacwork can be measured.

The device of this invention can be used both in an upright position,with the patient standing, and in a reclining position, with the patientlying down and exercising only his legs.

The machine also enables adjustment of the amount of work to be done andadaptation to different patients without large or difficult changes inthe machine.

Other objects and advantages of the invention will appear from thefollowing description of a preferred form thereof.

In the drawings:

FIG. 1 is a view in perspective of a cardiac exerciser embodying theprinciples of the present invention.

FIG. 2 is a fragmentary view in side elevation of the upper portion ofthe exerciser of FIG. 1 as adapted to a prone position, with theapparatus secured horizontally to an X-ray table.

FIG. 3 is a top plan view of the cardiac exerciser of FIG. 1 in uprightposition.

FIG. 4 is a view in front elevation of the upright cardiac exerciser ofFIG. 1.

FIG. 5 is a view in side elevation of the upright cardiac exerciser ofFIG. 1.

FIG. 6 is an enlarged view in section taken along the line 66 in FIG. 4.

FIG. 7 is a diagram of the hydraulic circuit.

The apparatus, when used in the standing position, incorporates a base10 which supports the remainder of the apparatus, including a centralcolumn or assembly 11, an instrumentation panel 12, handrails 13 and 14,and a pair of pedals 15 and 16. The handrails 13, 14 may be providedwith clamps 17 and 18 which may be used to fasten the device in ahorizontal position, rather than vertical, as shown in FIG. 2, byclamping the clamps 17 and 18 to the side edges 19 of an X-ray table 20,thereby placing the whole apparatus horizontally. Otherwise, theoperation is the same in both positions.

The handrails 13 and 14 are preferably comprised of hollow pipe, eachbent to shape to provide a pair of normally vertical base portions 21and 22 (attached removably to sleeves 23 and 24 of base brackets 25 and26), and a pair of angularly extending generally vertical portions 27and 28 which extend up and out to the side and are joined by a top rail32 to which the patient can hold. The clamps 17 and -18 are mounted tothe generally vertical portion 27. The handrails 13 and 14 may beunlocked and removed from the base 10 by releasing a latch mechanism 33on each bracket 25 or 26.

The central assembly 11 houses a pair of hydraulic cylinders 40 and 41,each having a piston 42 or 43 with a rod 44 or 45 extending therefrom.To each rod 44, 45, near its upper end, is secured a crosshand bar 46(FIG. 6) to which is attached a guide cylinder 47. An upper part 48 ofeach cylinder 40, 41 also acts as a guide cylinder having a pair ofslots 50 and 51 through which the bar 46 extends and along which it canmove up and down. Each guide cylinder 47 is connected by a member 3 49to a foot pedal or 16, one for each of the two cylinders and 41.

The hydraulic circuit (see FIG. 7) is such that the left pedal 15, whendepressed, also operates to raise the right foot pedal 16; and when theright pedal 16 is depressed, itoperates to raise the left foot pedal'15. The hydraulic cylinder 41 for the left pedal 15 is connected by acheck valve and conduit 61 to a load valve 56 which includes a chamber57 with a ball valve 58, normally urged into closed position by a spring59. From the valve 56 a conduit 64 leads by way of a check valve 63 tothe cylinder 40 for the right pedal 16, so that pressing on the leftpedal 15 sends a fluid under pressure through the first check valve 65to the load valve 56 and from there by the check valve 63 to the otherhydraulic cylinder 40. Similarly, the right hydraulic cylinder 40operates the same way through a check valve 62, a conduit 61, the loadvalve 56, the conduit 55, and a check valve 54, to the cylinder 41.

An adjustable foot-load is provided through the series of check valvesand the load valves. As the foot pedals 15 and 16 are worked up anddown, the hydraulic piston 42 or 43 on the downstroke forces the fluidto circulate through the check valve 65 or '62 and the load valve 56.The return fluid from the secondary side of the load valve 56 passesthrough the check valve 63 or 54 and returns to the cylinder 41 or 40 ofthe upstroke piston. This closed-circuit application has no reservoir oraccumulator.

Each of the cylinders 40 and 41 is provided with a step heightadjustment member 66 or 67, each of which is provided with a threadedlocking device 68 and is adapted to be set in any desired position, theheight being indicated on an outside portion 69. A stop 70 engages thetop of the rod 44 or 45 when that is at its upper height limit andtherefore sets that limit and hence the limit of the stroke.

The unit is self-contained and needs no outside connections, requires noelectricity or outside hydraulic or pneumatic equipment. Each of the twopistons 42 and 43 is connected to its respective foot pedal through theguide sleeve 47 which slides on the outside of the cylinder 40 or 41.The cylinders 40 and 41 have two functions: (1) retarding means for thefoot-load and (2) as a support and bearing column for the foot pedalstep-height travel. Self-lubricated nylon bearings provide a minimumfrictional resistance. Dual packings provide efiective seal against oilleakage.

The instrument panel 12 includes a timer 75, which may be a clock set inminutes and may or may not be provided with an alarm, depending on whatis desired, a gauge 76 for the foot-load in pounds, a cycle counter 77,and a foot-load regulator 78. The cylinder area may be sized to give onep.s.i. on the hydraulic pressure gauge 76 for a one pound foot-load. Inthis manner the hydraulic gauge 76 shows directly the actual foot pedalsetting and enables easy calculation of the energy output.

In use, load valve 56 may be set at a low pressure, the person to betested steps onto the pedals, and slowly starts stepping up and down asif climbing a stairway. During this preliminary operation the load valve56 is set by the regulator 78 to a desired gauge pressure which is alsothe pounds of foot-load for the person being tested. The step cyclecounter 77 is set to zero and the timer clock may then be started. Nowthe exact amount of work output in foot pounds exerted by the persontested can be calculated and recorded for future reference. As anexample, a ISO-lb. person being tested using a -lb. foot-load setting,and the maximum 8-inch step-height, in

ten minutes of test time the step-cycle counter may read 500 cycles. Onestep-cycle equals 16 inches or 1.33 feet of piston travel. Then theactual energy output is foot-pounds.

To those skilled in the art to Which this invention relates, manychanges in construction and widely differing embodiments andapplications of the invention will suggest themselves without departingfrom the spirit and scope of the invention. The disclosures and thedescription herein are purely illustrative and are not intended to be inany sense limiting.

We claim:

1. An exercising ergometer, including in combination:

supporting means,

a central column supported by said supporting means,

a pair of hydraulic cylinders carried by said supporting means, in saidcentral column, each having a piston and a connecting rod,

a pedal connected to each said connecting rod,

hydraulic circuit means connecting said cylinders and including loadvalve means for controlling the pressure transmitter, for causing onepedal to rise when the other is depressed, and

means for measuring the work expended in moving said' pedals.

2. The ergometer of claim 1 having means for limiting the stroke of saidpistons and of the pedals associated therewith, for changing the workper stroke.

3. A cardiac exerciser, including in combination:

a supporting base,

a pair of handrails secured to said base,

a central column, supported on said base midway between said handrails,

a pair of hydraulic cylinders in said central column,

each having a piston and a connecting rod,

a pedal on each side of said column, each connected to said connectingrod,

hydraulic circuit means connecting said cylinders and including loadvalve means for controlling the pressure transmitted, for causing onepedal to rise when the other is depressed, and

means for measuring the work expended in moving said pedals.

4. The exerciser of claim 3 having means for varying the stroke of saidpiston and of the pedal associated therewith.

5. The exerciser of claim 3 having means for detaching said handrailsfrom said base.

6. The exerciser of claim 3 having clamping means on said handrails forsecuring them to a table for horilzontal operation, said handrailsextending horizontally of ,the table and said column then likewiseextending horizontally.

References Cited UNITED STATES PATENTS 747,294 12/1903 Blaisdell 272-732,784,591 3/1957 Shoor 73-379 3,301,553 1/1967 Brakeman 12825 3,323,3666/1967 Lorme et al. 73379 3,375,717 4/1968 Impellizzeri et al. 73379RICHARD C. QUEISSER, Primary Examiner E. J. KOCH, Assistant ExaminerU.S. Cl. X.R. 27279

